(set-option :produce-interpolants 1)
(set-option :certify-interpolants 1)
(set-logic QF_LRA)
(set-info :status unsat)
(declare-fun a () Real)
(declare-fun b () Real)
(declare-fun c () Real)
(assert (!(and 
    (not (distinct a b c))
    (not (= a b))
(not (= a c))
):named A))
(assert (! (not (= b c)) :named B))
(check-sat)
(get-interpolants A B)
(exit)
